US4767880A - Process for racemizing optically active alpha-phenoxypropionic acid and derivatives thereof - Google Patents
Process for racemizing optically active alpha-phenoxypropionic acid and derivatives thereof Download PDFInfo
- Publication number
- US4767880A US4767880A US07/066,570 US6657087A US4767880A US 4767880 A US4767880 A US 4767880A US 6657087 A US6657087 A US 6657087A US 4767880 A US4767880 A US 4767880A
- Authority
- US
- United States
- Prior art keywords
- alkali metal
- carbon atoms
- employed
- chain length
- derivatives
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims description 14
- SXERGJJQSKIUIC-UHFFFAOYSA-N 2-Phenoxypropionic acid Chemical compound OC(=O)C(C)OC1=CC=CC=C1 SXERGJJQSKIUIC-UHFFFAOYSA-N 0.000 title description 5
- 229910052783 alkali metal Inorganic materials 0.000 claims abstract description 24
- -1 alkyl α-phenoxypropionates Chemical class 0.000 claims abstract description 16
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 claims abstract description 14
- 150000001340 alkali metals Chemical class 0.000 claims abstract description 13
- 229940031826 phenolate Drugs 0.000 claims abstract description 5
- HBAQYPYDRFILMT-UHFFFAOYSA-N 8-[3-(1-cyclopropylpyrazol-4-yl)-1H-pyrazolo[4,3-d]pyrimidin-5-yl]-3-methyl-3,8-diazabicyclo[3.2.1]octan-2-one Chemical class C1(CC1)N1N=CC(=C1)C1=NNC2=C1N=C(N=C2)N1C2C(N(CC1CC2)C)=O HBAQYPYDRFILMT-UHFFFAOYSA-N 0.000 claims abstract description 4
- 125000004432 carbon atom Chemical group C* 0.000 claims description 16
- 125000000217 alkyl group Chemical group 0.000 claims description 10
- 230000006340 racemization Effects 0.000 claims description 9
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 6
- 150000002148 esters Chemical class 0.000 claims description 6
- 229910052736 halogen Inorganic materials 0.000 claims description 6
- 150000002367 halogens Chemical group 0.000 claims description 6
- 125000003118 aryl group Chemical group 0.000 claims description 5
- 229910052739 hydrogen Inorganic materials 0.000 claims description 5
- 239000001257 hydrogen Substances 0.000 claims description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 4
- 125000003545 alkoxy group Chemical group 0.000 claims description 4
- 239000003153 chemical reaction reagent Substances 0.000 claims description 4
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 4
- 239000002904 solvent Substances 0.000 claims description 4
- 125000001424 substituent group Chemical group 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 3
- 125000006165 cyclic alkyl group Chemical group 0.000 claims description 3
- 150000002431 hydrogen Chemical class 0.000 claims description 3
- 229910052760 oxygen Inorganic materials 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 2
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 2
- 150000001335 aliphatic alkanes Chemical class 0.000 claims description 2
- 125000004104 aryloxy group Chemical group 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 150000001983 dialkylethers Chemical class 0.000 claims description 2
- 125000000623 heterocyclic group Chemical group 0.000 claims description 2
- 150000002576 ketones Chemical class 0.000 claims description 2
- 125000000449 nitro group Chemical group [O-][N+](*)=O 0.000 claims description 2
- 239000003960 organic solvent Substances 0.000 claims description 2
- 239000008096 xylene Substances 0.000 claims description 2
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 238000000354 decomposition reaction Methods 0.000 abstract description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 6
- 239000011541 reaction mixture Substances 0.000 description 6
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 4
- ILYSHPJWNMPBPE-QMMMGPOBSA-N ethyl (2s)-2-(4-hydroxyphenoxy)propanoate Chemical compound CCOC(=O)[C@H](C)OC1=CC=C(O)C=C1 ILYSHPJWNMPBPE-QMMMGPOBSA-N 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- BZLVMXJERCGZMT-UHFFFAOYSA-N Methyl tert-butyl ether Chemical compound COC(C)(C)C BZLVMXJERCGZMT-UHFFFAOYSA-N 0.000 description 3
- WQDUMFSSJAZKTM-UHFFFAOYSA-N Sodium methoxide Chemical compound [Na+].[O-]C WQDUMFSSJAZKTM-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- AQIHDXGKQHFBNW-UHFFFAOYSA-N 2-(4-hydroxyphenoxy)propanoic acid Chemical compound OC(=O)C(C)OC1=CC=C(O)C=C1 AQIHDXGKQHFBNW-UHFFFAOYSA-N 0.000 description 2
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 125000005907 alkyl ester group Chemical group 0.000 description 2
- 230000003197 catalytic effect Effects 0.000 description 2
- 238000004821 distillation Methods 0.000 description 2
- 230000007717 exclusion Effects 0.000 description 2
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 2
- 239000012074 organic phase Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- ZYVYEJXMYBUCMN-UHFFFAOYSA-N 1-methoxy-2-methylpropane Chemical compound COCC(C)C ZYVYEJXMYBUCMN-UHFFFAOYSA-N 0.000 description 1
- RMGHERXMTMUMMV-UHFFFAOYSA-N 2-methoxypropane Chemical compound COC(C)C RMGHERXMTMUMMV-UHFFFAOYSA-N 0.000 description 1
- ZAFNJMIOTHYJRJ-UHFFFAOYSA-N Diisopropyl ether Chemical compound CC(C)OC(C)C ZAFNJMIOTHYJRJ-UHFFFAOYSA-N 0.000 description 1
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 1
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical class [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 1
- 101100386054 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) CYS3 gene Proteins 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric Acid Chemical compound [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- 229960000583 acetic acid Drugs 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 150000001491 aromatic compounds Chemical class 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- QKYMWRPCHJECLZ-UHFFFAOYSA-N ethyl 2-hydroxy-2-phenoxypropanoate Chemical compound CCOC(=O)C(C)(O)OC1=CC=CC=C1 QKYMWRPCHJECLZ-UHFFFAOYSA-N 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000012362 glacial acetic acid Substances 0.000 description 1
- 239000004009 herbicide Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000012454 non-polar solvent Substances 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 229930195732 phytohormone Natural products 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- QDRKDTQENPPHOJ-UHFFFAOYSA-N sodium ethoxide Chemical compound [Na+].CC[O-] QDRKDTQENPPHOJ-UHFFFAOYSA-N 0.000 description 1
- NESLWCLHZZISNB-UHFFFAOYSA-M sodium phenolate Chemical compound [Na+].[O-]C1=CC=CC=C1 NESLWCLHZZISNB-UHFFFAOYSA-M 0.000 description 1
- 159000000000 sodium salts Chemical class 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 101150035983 str1 gene Proteins 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/487—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to chemical modification
Definitions
- the invention thus relates to a process for racemization of optically active enantiomers, wherein the compound of the general formula I, ##STR1## in which
- R 1 denotes an alkyl group, having up to 8 carbon atoms, which can in each case be substituted by hydroxyl, halogen, alkyl and/or nitro, or a cyclic alkyl group having up to 6 carbon atoms and
- R 2 denotes hydrogen, hydroxyl or an alkoxy group or an aryloxy group or an oxygen-bound, heterocyclic ring system, in each case having up to 10 carbon atoms, and
- R 3 and R 4 independently of one another, denote hydrogen or halogen
- alkali metal (C 1 -C 5 ) alcoholate an alkali metal hydroquinone, an alkali metal phenolate and/or an alkali metal hydroxyphenoxypropionate or derivatives thereof which carry substituents on the aromatic ring.
- the starting materials are the alkyl esters of ⁇ -phenoxypropionic acid and of the abovementioned derivatives thereof.
- the alkyl ester groups R 1 can contain up to 8 carbon atoms, which may be substituted, or, as a cyclic alkyl group, they can contain up to 6 carbon atoms. Lower linear alkyl groups having up to 5 carbon atoms, in particular unbranched alkyl groups having 1 to 3 carbon atoms are preferred.
- the optically active ester is employed dissolved in a solvent.
- a solvent Suitable for this are, for example, inert organic solvents in which the L- and D-esters are soluble.
- Hydrocarbons such as alkanes having a chain length up to 10 carbon atoms, and toluene or xylene, dialkyl ethers having a chain length up to 6 carbon atoms such as, for example, di-isopropyl ether, methyl isobutyl ether, methyl isopropyl ether and tert.butyl methyl ether, and dialkyl ketones having a chain length up to 6 carbon atoms, such as, for example, methyl ethyl ketone and methyl isobutyl ketone, are preferably used.
- Alcohols are furthermore preferred, the alcohol which corresponds to the chain length of the alkyl group R 1 of general formula I being employed in particular.
- racemization is carried out by adding an alkali metal (C 1 -C 5 ) alcoholate, preferably an alkali metal (C 2 -C 4 ) alcoholate, an alkali metal hydroquinone, an alkali metal phenolate or an alkali metal hydroxyphenoxypropionate.
- Derivatives of the aromatic compounds mentioned can also be used, in particular those which carry, on the aromatic ring, up to two additional substituents which, independently of one another, are hydrogen, halogen, alkyl and alkoxy.
- the reagents are employed in concentrations of 1 to 10 mole percent, preferably 3 to 8 mole percent. If ⁇ -phenoxypropionic esters, or derivatives thereof with alkali metal (C 1 -C 5 ) alcoholates, are racemized, more than 1.0 mole of base per mole of ester must be employed. Using the other reagents mentioned, catalytic amounts are required. The reaction mixture is heated to 100 to 200° C. and incubated for 30 minutes to 8 hours, preferably 2 to 4 hours.
- the racemization is carried out using alkali metal (C 1 C 5 ) alcoholate, the acid is obtained essentially quantitatively as the final product in an alkaline medium, or as the ester in an acidic medium.
- the final products are separated off from the reaction mixture by methods which are known per se, by acidification and extraction with a relatively nonpolar solvent, such as, for example, diethyl ether, in the case of the acid, or, for example, by distillation in the case of the ester.
- a relatively nonpolar solvent such as, for example, diethyl ether
- Example 3 An analogous procedure to Example 3 was carried out, with addition of 100 mg of sodium phenolate. After working up, 2.5 g of racemic ethyl D,L-2-(4-hydroxyphenoxy)propionate were obtained.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19863621835 DE3621835A1 (de) | 1986-06-28 | 1986-06-28 | Verfahren zur racemisierung optisch aktiver (alpha)-phenoxypropionsaeure und deren derivate |
| DE3621835 | 1986-06-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4767880A true US4767880A (en) | 1988-08-30 |
Family
ID=6304010
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US07/066,570 Expired - Fee Related US4767880A (en) | 1986-06-28 | 1987-06-26 | Process for racemizing optically active alpha-phenoxypropionic acid and derivatives thereof |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4767880A (de) |
| EP (1) | EP0251058A3 (de) |
| JP (1) | JPS638351A (de) |
| DE (1) | DE3621835A1 (de) |
| DK (1) | DK328887A (de) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4946997A (en) * | 1989-06-07 | 1990-08-07 | Merck & Co., Inc. | Racemization of a carboxylic acid |
| US5221765A (en) * | 1992-01-24 | 1993-06-22 | Ethyl Corporation | Racemization process for an optically active carboxylic acid or ester thereof |
| US5278338A (en) * | 1992-11-04 | 1994-01-11 | Ethyl Corporation | Racemization process for optically active carboxylic acids, salts and esters |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69015000T2 (de) * | 1989-06-07 | 1995-06-14 | Nippon Telegraph & Telephone | Optisch aktive Verbindungen und sie enthaltende Flüssigkristallzusammensetzungen. |
| JP2507163B2 (ja) * | 1989-10-06 | 1996-06-12 | 株式会社クラレ | 光学活性４―フェニル酪酸エステル誘導体のラセミ化方法 |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3717669A (en) * | 1968-06-18 | 1973-02-20 | American Home Prod | 2-phenoxyalkanoic acid esters |
| US3759950A (en) * | 1971-09-20 | 1973-09-18 | American Home Prod | 2-phenoxyalkanoic acid esters |
| JPS6183144A (ja) * | 1984-09-28 | 1986-04-26 | Nissan Chem Ind Ltd | ２−（４−ヒドロキシフエノキシ）プロピオン酸の光学分割法 |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57171938A (en) * | 1981-04-15 | 1982-10-22 | Nissan Chem Ind Ltd | Preparation of optically active naphthylpropionic acid ester |
| DE3319367A1 (de) * | 1983-05-27 | 1984-11-29 | Bayer Ag, 5090 Leverkusen | Optisch aktive diphenylether-derivate |
-
1986
- 1986-06-28 DE DE19863621835 patent/DE3621835A1/de not_active Withdrawn
-
1987
- 1987-06-19 EP EP87108778A patent/EP0251058A3/de not_active Withdrawn
- 1987-06-26 JP JP62157985A patent/JPS638351A/ja active Pending
- 1987-06-26 DK DK328887A patent/DK328887A/da not_active Application Discontinuation
- 1987-06-26 US US07/066,570 patent/US4767880A/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3717669A (en) * | 1968-06-18 | 1973-02-20 | American Home Prod | 2-phenoxyalkanoic acid esters |
| US3759950A (en) * | 1971-09-20 | 1973-09-18 | American Home Prod | 2-phenoxyalkanoic acid esters |
| JPS6183144A (ja) * | 1984-09-28 | 1986-04-26 | Nissan Chem Ind Ltd | ２−（４−ヒドロキシフエノキシ）プロピオン酸の光学分割法 |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4946997A (en) * | 1989-06-07 | 1990-08-07 | Merck & Co., Inc. | Racemization of a carboxylic acid |
| US5221765A (en) * | 1992-01-24 | 1993-06-22 | Ethyl Corporation | Racemization process for an optically active carboxylic acid or ester thereof |
| US5278338A (en) * | 1992-11-04 | 1994-01-11 | Ethyl Corporation | Racemization process for optically active carboxylic acids, salts and esters |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0251058A2 (de) | 1988-01-07 |
| DK328887A (da) | 1987-12-29 |
| EP0251058A3 (de) | 1988-12-14 |
| JPS638351A (ja) | 1988-01-14 |
| DK328887D0 (da) | 1987-06-26 |
| DE3621835A1 (de) | 1988-01-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: HOECHST AKTIENGESELLSCHAFT, D-6230 FRANKFURT AM MA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:WULLBRANDT, DIETER;SCHLINGMANN, MERTEN;REEL/FRAME:004729/0872 Effective date: 19870602 Owner name: HOECHST AKTIENGESELLSCHAFT, A CORP. OF GERMANY,GER Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WULLBRANDT, DIETER;SCHLINGMANN, MERTEN;REEL/FRAME:004729/0872 Effective date: 19870602 |
|
| FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
| REMI | Maintenance fee reminder mailed | ||
| LAPS | Lapse for failure to pay maintenance fees | ||
| FP | Lapsed due to failure to pay maintenance fee |
Effective date: 19920830 |
|
| STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |